Meter devices and methods

Abstract

Some embodiments of a meter device for measuring volume flow of gas can include bearings and the timing gears may each include a least one component comprising a ceramic material that enhances the wearability of the bearing and the timing gears. Accordingly, the gas flow meter can operate in a manner that reduces or eliminates the need for external oil lubrication of the bearings and the timing gears (e.g., the external oil lubrication conventionally provided by the oil bath compartment), and thus reduces the likelihood of failure of the gas flow meter due to leaks or failures of the oil bath compartment.

1. A meter device for measuring volume flow of gas, comprising:
 a flow meter housing having an inlet and an outlet through which a fluid flows to rotate first and second impellers; 
 first and second shafts in the housing that rotates in response to rotation of the first and second impellers, the first shaft being rotatably supported in the housing by at least a first roller bearing, the second shaft being rotatably supported in the housing by at least a second roller bearing, wherein each of the first and second roller bearings includes metal raceways that engage with ceramic rolling elements; and 
 first and second timing gears having an exterior ceramic coating and that rotate in response to rotation of the first and second shafts, wherein the timing gears engaging one another along the exterior ceramic coating in an oil-less environment in which space surrounding the timing gears is free of oil. 
 
     
     
       2. The meter device of  claim 1 , wherein the first and second impellers are rotated in a predetermined timing pattern that is dictated by the first and second timing gears having the exterior ceramic coating. 
     
     
       3. The meter device of  claim 2 , wherein the exterior ceramic coating of the first and second timing gears comprises a silicon nitride material. 
     
     
       4. The meter device of  claim 1 , wherein the ceramic rolling elements of the first and second roller bearing comprises a silicon nitride material. 
     
     
       5. The meter device of  claim 4 , wherein the raceways of the first and second roller bearings comprises a steel material. 
     
     
       6. The meter device of  claim 5 , wherein the ceramic rolling elements of the first and second roller bearings is impregnated with a lubricant before the first and second roller bearings rotatably support the first and second shaft in the housing. 
     
     
       7. The meter device of  claim 1 , further comprising a meter readout unit coupled to the flow meter housing, the meter readout unit including an input shaft that is driven to rotate in response to rotation of the timing gears, the meter readout unit comprising a display window that indicates numeric indicia of an amount of fluid flow through the housing. 
     
     
       8. A method of operating a gas flow meter device, comprising:
 rotating first and second impellers in a gas flow meter housing as a gas is advanced from an inlet to an outlet, the first impeller being supported by a first shaft rotatably mounted in the housing, and the second impeller being supported by a second shaft rotatably mounted in the housing; 
 in response to rotation of the first and second impellers, causing first and second hybrid bearing assemblies to rotate in the housing such that ceramic rolling elements contained in each of the hybrid bearing assemblies engage with metal raceways, the first hybrid bearing assembly rotatably supporting the first shaft in the housing and the second hybrid bearing assembly rotatably supporting the second shaft in the housing; and 
 in response to rotation of the first and second impellers, causing first and second timing gears having an exterior ceramic coating to rotate and engage one another in an oil-less environment in which space surrounding the timing gears is free of oil. 
 
     
     
       9. The method of  claim 8 , wherein the step of rotating the first and second impellers comprises rotating the first and second impellers in a predetermined timing pattern that is dictated by the first and second timing gears having the exterior ceramic coating. 
     
     
       10. The method of  claim 9 , wherein the exterior ceramic coating of the first and second timing gears comprises a silicon nitride material. 
     
     
       11. The method of  claim 8 , wherein the ceramic rolling elements of the first and second roller bearing comprises a silicon nitride material. 
     
     
       12. The method of  claim 11 , wherein the raceways of the first and second roller bearings comprises a steel material. 
     
     
       13. The method of  claim 12 , wherein the ceramic rolling elements of the first and second roller bearings is impregnated with a lubricant before the first and second roller bearings rotatably support the first and second shaft in the housing. 
     
     
       14. The method of  claim 8 , further comprising driving a meter readout unit to output numeric indicia of an amount of fluid flow through the housing, the meter readout unit being coupled to the meter housing and including an input shaft that is driven to rotate in response to rotation of the timing gears.